|
| US3955425 | 16. Aug. 1974 | 11. Mai 1976 | Indev, Inc. | Pipe wall thickness gauge |
| US4041773 | 8. Okt. 1975 | 16. Aug. 1977 | W. C. Lamb | Ultrasonic inspection apparatus for well operations |
| US4439730 | 8. Mai 1981 | 27. März 1984 | AMF Inc. | Nondestructive inspection apparatus and method utilizing combined inspection signals obtained from orthogonal magnetic fields |
| US4641092 | 5. Juli 1983 | 3. Febr. 1987 | Sumitomo Metal Industries, Ltd. | Rotary probe apparatus for detecting flaws in a test object |
| US5334934 | 31. Dez. 1992 | 2. Aug. 1994 | General Electric Company | Eddy current probe apparatus and interlaced scanning method for interior inspection of metal devices |
| US5412319 | 11. März 1993 | 2. Mai 1995 | Ceda SpA Construzioni Elettromeccaniche e Dispositivi d'Auto-mazione | Device to detect disturbances in an electromagnetic field induced by surface faults in a metallic bar or wire rod in movement |